Voxel had such a ridiculous amount of money towards the end of that campaign because the GM was handing it out like candy and technomancers don’t have any of the expenses the other archetypes face regularly (decks, augments, magical materials, etc.). The only advice anyone else could give me was “a Scrooge McDuck-style pool of drugs” (thanks, Ko) but I mostly spent it on any gadget that looked halfway useful (nearly none of them ever got used, but a few did) and extra identities and safehouses for when shit inevitably hit the fan.
At one point he was prepared to sink tens of thousands into hiring a rigger to kill the Govenor, Face and Mage, but the rigger got caught (without enough info about who hired him to get Voxel caught too) so he didn’t even end up having to pay him.
Eventually I asked the GM if I could hire a mage to perma-cast huge boosts on Voxel’s mental stats, so I sunk lots of money into that to let him walk around with a constant +4 to Charisma and Willpower. Shame those spells fell away when he left Earth.